Variable-resistance switch



" S pt. 4, 1928. 1,683,280

J. L. ARTHUR VARIABLE RESISTANCE SWITCH Filed 001:.29, 1925 Sept. 4,1928. 1,683,280 J. L. ARTHUR I VARIABLE RESISTANCE SWITCH Fil 2 1925 2Sheets-Sheet 2 Patented Sept. 4, 1928.

PATENT OFFICE.

J'AIES L. ARTHUR, OI ANDERSON, INDIANA, ASSIGNOR, BY HESNE ASSIGNMENTS,TO DELOO-BEIY CORPORATION, 01 DAYTON, OHIO, A CORPORATION 01? DELAWARE.

VARIABLE-RESISTANCE SWITCH.

Application filed October 29. 1925. Serial No. 85.670.

This invention relates to electrical starting apparatus forinternaleombustwn engines and particularly to the type of apparatuswhich comprises an electric motor, a

spirally-splined shaft driven by the motor, and a pinion screw-threadedupon said shaft and adapted to move endwise along' the shaft intoengagement with a gear of an'engme to be started. The inion is moved1nto partial engagement wlththe engine gear by manual operation and thenthe motor turns the splined shaft in a direction to cause the pinion tobe threaded into full engagement with the engine gear and into contactwith a stop whereu on the pinion drives the eng ne gear to cran theengine. After the engine becomes self-operative the pinion isautomatically disconnected from the engine. In

devices of this sort it is desirable that the motor be operated onlywith partial ower until the pinion is substantially fu ly in mesh withthe engine gear at which time the full power of. the motor may beapplied to crank the engine. Such an arrangement practically eliminatesbreakage of gear. teeth due to full power operation of the motor whilethe gears are being meshed. I

One of the objects of the present invention is to provide for. this typeof apparatus an improved motor-controlling switch which willv cooperatewith the apparatus, so that the pinion will be operated first with lowspeed and power to facilitate gear meshing by manual operation, andfurther and more complete engagement of the pinion withthe engine gearby motor operation, sald controller being adapted to apply the fullpower of the motor after the meshing of the gears is substantiallycompleted.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being bad to the accompanyingdrawings, wherein-a preferred form of the present invention 1s clearlyshown.

In the drawings:

Figs. 1, 2 and 3 are side views partly in section of a startingapparatus embodying I the present invention and showing the appa- 50ratus in three different positions of opera' tion.

Fig. 4 is a sectional view on the line 4-4 of Fig. 1.

Fig. 5 is a sectional view on the line 55 of Fig. 4.

Fig.6 is a sectional view on the line 6-6 of Fig. 5. Referring to thedrawings, 20 designates afield frame of an electric motor which issupported by a gear housing 21 which is. adapted to be attached to theframe of an engine to be started. The housing 21 provldes a bearing 22for the armature shaft of the motor, the otherbearing being providedwith an end frame (not shown), secured to the other end of the motorframe 20. The shaft 23 supports an armature-24 and is provided with ashouldered portion 25 and with a spirally-splined portion 26. A thrustcollar 27 is secured to a shaft by pin 28 and bears against a thrustwasher 29. This in turn bears against a finished surface 30 of the gearhousing 21. A pinion 31 is thread edly connected with the spline 26 soas to move endwise along the shaft 23 and turn with the shaft after thepinion has been moved against the collar 27. In order to move the pinionendwise, the 'inion is provided with a hub 32 provided with spacedflanges 33 defining an annular groove 34. The groove 34 receives thearms 35 of.a bifurcated pinion-shifting lever 36 having a yoke 37. Thearms 35 are provided .with rectangular openings 38 for receiving andguiding the ends of a latch plate 39. The latch plate 39 is connectedwith studs 40 which pass freely through openings in the yoke 37 andcarry at their outer ends washers 41. Springs 42 are located between thewashers 41 and yoke 37; thus, it will be seen that if the latch plate 39is moved to the right, motion will be transmitted through the spring 42throu h theyoke 37.

The mechanism or moving the yoke 37. and latch plate 39, includes apedal 43 connected by pedal rod 44 with a pedal lever 45 which carriesat its lower end a rod 46 providing a ivot for a latch 47 which isprovided wit a hook 48 for engaging the latch plate 39. The yoke 37 isrovided with an 100 opening 49 for receiving t e hook 48. The latch 47is held normally in the position shown in Fig. 1 by a sprmg 50 havingone end connected by screw 51 with the-housing 21 and having the otherend bent, as indi- .cated in Fig. 6 by numeral 51., so as to ex- (illdemesh tend through a hole in latch 47 located below the pivot rod 46.The spring 50 is biased so that, normally, it will urge the latch in acounterclockwise direction when the pedal is in the position shown inFig. 1. By moving the pedal downwardly, so that the pinion 31 is broughtinto partial engagement with the engine gear 52, the spring 50 will bereconditioned so that it will tend to urge the latch in a clockwisedirection relative to its pivot rod46. The latch does not start to moveinto a counterclockwise direction as soon as the spring 50 isreconditioned to produce this result, since the spring is resisted bypressure between the hook of the latch and the latch plate, due topressure upon the pedal 43. However, when the pinion 31 is moved endwiseinto mesh with the gear 52 due to the operation of the motor independentof the pedal 43, this pressure will be released, so that when the pinionis in full engagement with the engine gear, as shown in Fig. 3, thelatch will be entirely disengaged from the latch plate. This mechanismhas been provided in order that the pinion may be demeshed automaticallyregardless of failure of the operator to release the pedal 43.

' By a controlling apparatus associated with the pedal lever 45,themotor is caused to turn slowly at firs; to facilitate meshing theinion 31 with the gear 52, and o operate witlow torque but which issufiicient to cause the pinion to he threaded ii the position in Fig. 2to the full-mesh position shown in n the moved to (251139618. mo to operpower, in order to the engine becomes so shown in Fig. 1 althoc lull mayremain. ie po A spring 5 ving c.

coiled upon the rod levers 45 hearing respectively st the hon indicatedat 55, and a a 39, as indicated 565, causes the he urged in clockwisedirection as pinion huh 32 will he maintained against the shoulder Afterthe pecla is re leased a spring located between the pedal 43 and acup-shaped rnernher 6Z1 to the fioorhoard 62 of the vehicle causes the21, l. och plate pedal 43 and lever 45 to return to the position shownin Fig. During re return n 4'? moves the lever 36 and .e latch plate 89as movement of the lever 45, the late through the yoke 37 snaps intoposition ovei shown in Figs. 1 and 5.

The controller for controlling the motor circuits comprises main andauxiliary switches which are housed within a case mounted upon the frame26 of the motor. The main switch it. .ee contact provided the pinionalong by the head 71 of a main switch terminal bolt 72 which isinsulatingly supported by the case 70, and a movable contact 73 which isadapted to connect the contact 71- with a stationary contact 74 attachedto the terminal screw 75 of the motor. The auxiliary switch includes astationary contact 76 connected with the bolt 72 and insulated from thecase 7 0, a movable contact 77 and a stationary contact 7 8 which isintegral with the part which forms the cont-act 74. The contact 7 3 ismade of a low resistance material such as copper, and the contact 77 ismade of a relatively high resistance material such as carbon. Thesecontacts are insulatingly supported upon a plunger 79 which is supportedand guided by a. sleeve 80 carried by the switch case. The contact 73 islocated loosely on the reduced lower end 81 of the plunger 79 and isfree to move sidewise between a nut 82, attached to the plunger 79,

and a shoulder 83 of the plunger. In this way the contact 73 is free toaccommodate itself to the surface of the contacts 71 and 74. The carboncontact 7 7 is swingingly supported by the plunger 7 9 so that contact 77 may tilt slightly to accommodate itself to the contacts 7 6 and 78. Aspring 84, located hetween the case 70 and a flangeor button. 85attached to the plunger 7'9, yieldingly maintains the contact 73 inengagement withnonconducting washers 86 in turn hear against the carboncontac 77 and causeit to hear against insulati e lower end of the sleeve80.

opposed by a weaker n the washer 87 and a in.

a tube which receives and en :te 1e sleeve 86.. e spri 88 yieldinglyv escontact 77 aid the contact 7 3.

Th 4 J.

non o e pedal lever 45 to cause the move into a zeo. with the motor cecontact 77. The te with relatively to facilitate engine gear and i to ote with no more Jed. on oi; the threading it into engage- 27.

will cause the s time the gears ned. Then the .ll power to crank ofbreaking gear lOW of the L cause the power than.

with the the engine without dan e: teeth.

As stamd before failure to release the pedal 43 when engine becomes selfoperative does not prevent demesliing of the ears since the latch isdisconnected irom the atch plate and the pinion shifting lever is freeto move toward the left. v

washer 87 which Continued v Release of the pedal 43 causes the spring 60to restore the pedal lever 45 to the position shown in Fig. 1, andrelease of the plunger 79 allows the spring 80 to return the movableswitch parts into the position shown in Fig. 1.

In case the engine should fail to star after the gears have been meshedand the switches have been closed, the pedal 43 may be released and sring 60 will cause the pedal to move upwardly first to permit theopening of the main switch and then to cause the pedal lever 45 to pushthe latch 47 and hence the lever 36 to the left (in the drawings) todemesh the gears and to open the auxiliary switch.

While the form of embodiment of the present invention as hereindisclosed, constitutes a preferred form, it is to be understood thatother forms might be adopted, all coming within the scope ofthe claims'which follow.

What is claimed is as follows:

1. An electric switch comprising a rod, a case supporting and guidingthe rod, a relatively low total resistance contact mounted adjacent oneend of the rod, a relatively high total resistance contact slidable uponthe rod, a pair of contacts located in the path of movement of the highresistance in a direction for separating the movablecontacts from thestationary switch contacts.

2. An electric switch comprising pairs of stationary contacts, a rigid,high total resistance-contact for bridging one air of stationarycontacts, a low total resistance contact for bridging the other pair ofcontacts, a spring urging the high resistance contact towardswitch-closing position,- an operating member movable in one directionfor retaining the high resistance contact in switchopen position andmovable in the other direction first to permit said high resistancecontact to be moved 'by said spring into switchclosing position and thento move the low resistance contact into switch-closing position, and aspring for resisting the last described movement of the operatingmember.

In testimony whereof I hereto aflix my signature. 7

JAMES LpARTHUR.

